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Although the United States has focused its efforts on defeating the Islamic State (also known as ISIS), al Qaeda has quietly lingered on and is attempting to make a comeback. But whether it will succeed is up for debate. Assessments about its future vary between two broad camps. Some, such as Georgetown University's Daniel Byman, maintain that the group has been in decline because of limited popular support, effective counterterrorism efforts by the United States and other countries, and al Qaeda's killing of Muslim civilians. He concludes that there is “good reason to be optimistic that al Qaeda's decline is for real and might even be permanent.”

Others, such as former FBI agent Ali Soufan, disagree. Soufan contends that al Qaeda is transitioning from a small terrorist outfit with struggling affiliates to a potent transnational network of branches that has gained in numbers and fighting strength and now spans the Middle East, Africa, and Asia. Daveed Gartenstein-Ross of the Foundation for Defense of Democracies argues that the group has “emerged stronger by pursuing a strategy of deliberate yet low-key growth.”

But many such predictions about whether al Qaeda will resurge or further decline are presumptuous because they fail to identify the most important factors that could impact its trajectory. Al Qaeda's past strength has never been linear, but has waxed and waned based on such factors as the collapse of governments in countries such as Iraq, Syria, and Yemen. Consequently, the initial task in analyzing al Qaeda's future is a methodological one: to identify those factors that could affect its future path. Most of the debate about the future of al Qaeda or the Islamic State has lacked such an analytical approach, and policymakers and academics have too quickly jumped to conclusions about whether al Qaeda will strengthen or weaken, which is mostly guesswork.

In this regard, al Qaeda's revival will likely hinge on its ability to take advantage of future opportunities such as the withdrawal of small numbers of U.S. or other Western counterterrorism forces from key battlefields such as Afghanistan, Iraq, and Syria; more revolt in the Middle East or even a second Arab Spring; U.S. or European policies or actions that feed the perception of Muslim oppression; the rise of another charismatic al Qaeda or other jihadist leader; a large-scale conventional deployment of U.S. or other Western military forces, however unlikely at the moment, to the Middle East or South Asia; or the collapse of ISIS in the Middle East, Africa, or Asia. Al Qaeda's further decline will likely be caused by the absence of these opportunities or the movement's failure to take advantage of them.

Al Qaeda's Ebb and Flow

In 1988, Osama bin Laden, Ayman al-Zawahiri, and other leaders established al Qaeda to combat Soviet forces in Afghanistan.

Al Qaeda's rise came in four waves. In 1988, Osama bin Laden, Ayman al-Zawahiri, and other leaders established al Qaeda to combat Soviet forces in Afghanistan. Ten years later, on August 7, 1998, al Qaeda perpetrated simultaneous attacks against the U.S. embassies in Nairobi, Kenya, and Dar es Salaam, Tanzania. Al Qaeda operatives then bombed the USSCole on October 12, 2000, while it was refueling in Yemen. The attack killed 17 U.S. soldiers and injured 39 others. This first wave of attacks peaked in 2001 with September 11. Over the next two years, al Qaeda faced a reversal as the United States and its allies captured or killed its leaders and operatives in Afghanistan, Pakistan, the United States, and across the globe.

A second wave began to build in 2003 after the U.S. invasion of Iraq. Abu Musab al-Zarqawi and his group, Jamaat al-Tawhid wal-Jihad, began an aggressive insurgency campaign against the United States and its allies. Zarqawi then joined al Qaeda in 2004. Outside of Iraq, the group conducted attacks in such countries as Indonesia, Morocco, Saudi Arabia, and Turkey. In March 2004, North African terrorists inspired by al Qaeda's ideology conducted coordinated bombings against the commuter train system in Madrid, Spain, killing nearly 200 people and injuring approximately 200 others. In July 2005, al Qaeda pulled off one of its most audacious attacks in Europe as suicide bombers targeted three trains in the London Underground and a double-decker bus. The attack killed over 50 people and wounded another 700. But by 2006, al Qaeda in Iraq had been severely weakened, British and American intelligence agencies had foiled several plots, and U.S. drone strikes had killed senior al Qaeda operatives in Pakistan.

Al Qaeda surged for a third time between 2007 and 2009 following the rise of Anwar al-Awlaki, a charismatic Yemeni-American who had served as an imam in mosques in California and Virginia, and the emergence in Yemen of al Qaeda in the Arabian Peninsula. On November 5, 2009, Nidal Hasan, a U.S. Army major who was in contact with Awlaki, gunned down 13 people and wounded 43 others at Fort Hood, Texas. The next month, Umar Farouk Abdulmutallab attempted to blow up Northwest Airlines Flight 253, which was flying from Amsterdam to Detroit. The bomb ignited, but the main charge failed to go off. That same year, Najibullah Zazi, a U.S. citizen from New York, was arrested for plotting to bomb the New York City subway after meeting with senior al Qaeda leaders in Pakistan. The reversal of this wave began with the 2011 killing of Osama bin Laden and the deaths of other senior al Qaeda leaders following an aggressive U.S. drone campaign.

The Arab Spring and the downsizing or withdrawal of U.S. forces from Iraq and Afghanistan created the conditions for a fourth wave, as al Qaeda affiliates expanded their presence in countries such as Afghanistan, Somalia, Syria, and Yemen. Most of the al Qaeda attacks in the fourth wave occurred in “near enemy” countries, not in the West. But the group weakened in 2014 after the rise of ISIS, which was formerly al Qaeda in Iraq.

Affiliate Groups

Al Qaeda remains a loose, overlapping, and fluid network across multiple regions. Ayman al-Zawahiri is al Qaeda's leader, flanked by general manager Abd al-Rahman al-Maghrebi and senior manager Abu Muhsin al-Masri. The group's nominal leadership appears to have limited legitimacy and influence over an organization that has five affiliates: Jabhat al-Nusrah in Syria; al Qaeda in the Arabian Peninsula in Yemen; al Qaeda in the Indian Subcontinent in South Asia; al Shabaab in Somalia; and al Qaeda in the Islamic Maghreb in North Africa. In addition, the group retains an active relationship with groups across Africa, the Middle East, and Asia such as Ahrar al-Sham in Syria, the Taliban and Haqqani Network in Afghanistan, Tehreek-e-Taliban Pakistan in Pakistan, and Jamaat Nusrat al-Islam wal Muslimeen in the Maghreb and West Africa.

Among al Qaeda's most active affiliates are those in Afghanistan, Syria, and Yemen.

Among al Qaeda's most active affiliates are those in Afghanistan, Syria, and Yemen. In Syria, Jabhat al-Nusrah remains an important component of the insurgency against the Syrian regime. In January 2017, it cooperated with elements of Ahrar al-Sham and other groups to form Hay'at Tahrir al-Sham, but Jabhat al-Nusrah continues to effectively function as al Qaeda's Syria branch, with as many as 10,000 fighters.

In Yemen, al Qaeda in the Arabian Peninsula has tried to expand its foothold in the Abyan, Marib, and Shabwah governorates with upwards of 4,000 fighters. In April 2017, Qasim al-Raymi, the group's leader, outlined his strategy of building broad and deep support among Sunni groups and tribes in Yemen: “We fight [alongside] all Muslims in Yemen, together with different Islamic groups. We fought with the Salafs without exception. We fought with the Muslim Brotherhood and also our brothers from the sons of tribes. We fought together with the public in Aden and elsewhere. We participate with the Muslims in every battle.”

In September 2014, Zawahiri announced the creation of a new affiliate, al Qaeda in the Indian Subcontinent, which oversees activities in Afghanistan, Bangladesh, India, and Pakistan. The group is led by Asim Umar, a former member of Harkat-ul-Jihad al-Islami, a Pakistan-based terrorist group with branches across the Indian subcontinent. Umar is flanked by Abu Zar, his first deputy, and oversees perhaps 200 fighters.

Despite al Qaeda's persistence, the movement has conducted few successful attacks in the West over the past several years. Unlike ISIS, al Qaeda has also failed to inspire many attacks overseas. One of the last major al Qaeda plots in the U.S. homeland occurred nearly a decade ago, when Najibullah Zazi and two accomplices prepared to conduct suicide attacks on the New York City subway. But it was foiled by U.S. and British intelligence and law enforcement agencies. Chérif Kouachi, who trained in Yemen with al Qaeda in the Arabian Peninsula, was involved in the January 2015 attack against the French satirical weekly newspaper Charlie Hebdo in Paris. The attack killed 12 people and injured 11 others. But the Charlie Hebdo attack was an outlier, since most of al Qaeda's violence of late has been directed at targets in “near enemy” countries such as Kenya, Somalia, Syria, and Yemen.

A Coming Resurgence?

It is unclear whether al Qaeda will be able to establish a fifth wave as the group's leaders still seek to establish a caliphate that extends from Africa through the Middle East to Asia. Several factors may impact the rise—or decline—of al Qaeda over the next several years. Most of these factors are outside of al Qaeda's control, although much will depend on how it or other Salafi-jihadist groups respond to them.

The withdrawal of U.S. or other Western military forces from jihadist battlefields could contribute to a resurgence.

First, the withdrawal of U.S. or other Western military forces—particularly special operations forces and air power—from jihadist battlefields could contribute to a resurgence. Examples include the withdrawal of U.S. or other Western forces from Afghanistan, Iraq, Somalia, and Syria. In at least two of these countries—Syria and Afghanistan—some Trump administration officials have questioned the wisdom of a long-term U.S. commitment. U.S. actions in these countries, however limited, have served as a check against al Qaeda and other terrorist organizations. The U.S. and Soviet exit from Afghanistan in the late 1980s and early 1990s contributed to the country's further deterioration and the rise of the Taliban and al Qaeda. The U.S. withdrawal from Iraq in 2011 contributed to a resurgence of al Qaeda, the rise of ISIS, and the spread of extremist ideology across the region.

Second, another Arab Spring or the collapse of one or more governments in the Arab world might allow al Qaeda to strengthen. Instability in some countries (such as Egypt, Jordan, Saudi Arabia, and Tunisia) or continuing war in others (such as Afghanistan, Iraq, Libya, Somalia, or Syria) could provide al Qaeda or other jihadist groups with key sanctuaries. Among the most significant reasons for al Qaeda's fourth wave was a weakening of governance during the Arab Spring.

Third, events that highlight the oppression of Muslims by Western governments could give potential propaganda opportunities to al Qaeda. In 2004, the story broke of abuse and humiliation of Iraqi inmates by U.S. soldiers at the Abu Ghraib prison. The uncensored photographs appeared on jihadist websites and were used for recruitment purposes. A similar atrocity could be used by Salafi-jihadist groups for propaganda. In addition, the United States or other Western countries could overreact to a terrorist attack on their soil and implement domestic policies that broadly target Muslims and create a perception of a so-called war against Islam. Such a development could increase radicalization and recruitment for al Qaeda and other groups.

In May 2017, al Qaeda labeled bin Laden's son Hamza a “shaykh,” suggesting that it might be considering him for leadership.

Fourth, the rise of a charismatic al Qaeda leader might help revitalize the movement. Osama bin Laden was an inspirational leader, as was Anwar al-Awlaki. But current leader al-Zawahiri has been far less charismatic. This, however, could change. In 2016, al Qaeda leaders began to promote one of bin Laden's sons, Hamza, in their propaganda. In May 2017, the group labeled Hamza bin Laden a “shaykh,” suggesting that it might be considering him for leadership. Although it is unclear whether he will be charismatic enough, his leadership could potentially help increase global support for the movement.

Fifth, a large-scale deployment of U.S. or other Western military conventional forces to Islamic battlefields, however unlikely, could increase the possibility of a resurgence by al Qaeda or other groups. The U.S. deployment of conventional forces to fight terrorists overseas has generally failed to stabilize countries and has often been counterproductive. In Iraq, for instance, the U.S. conventional presence contributed to radicalization. Large numbers of U.S. forces in Muslim countries can facilitate terrorist recruitment by increasing local fears of foreign occupation, enabling terrorist recruiters to attract foot soldiers in order to defend Islam.

Many of the extremists involved in U.S. homeland plots after September 11, 2001—such as José Padilla, Nidal Hassan, Najibullah Zazi, and Faisal Shahzad—were motivated, in part, by the deployment of large numbers of U.S. combat troops in Muslim countries. At the moment, it is unlikely that the Trump administration or the U.S. population would support the large-scale deployment of military forces to fight terrorism. But some Americans might rethink this possibility after a major terrorist attack on U.S. soil.

Sixth, the collapse of ISIS—particularly the core of its so-called caliphate in Iraq and Syria—might allow al Qaeda or other groups to rejuvenate. The further weakening or collapse of ISIS could also increase the possibility of a merger between fighters loyal to both al Qaeda and the Islamic State under one umbrella—or even to the emergence of a new Salafi-jihadist group.

A Resilient Ideology

Al Qaeda today is a different organization from what it was even a decade ago. The movement is less centralized, less focused on terrorist operations in the West for the moment, and less popular. Based on these challenges, it is unclear whether al Qaeda or other Salafi jihadists will be able to rebound. Even if there is a resurgence, it could be led by al Qaeda, ISIS, a new organization, or a mix of Salafi jihadist groups. Such a revival will likely hinge on the ability to take advantage of opportunities that emerge, such as the collapse of one or more Arab governments. But the Islamist extremism that al Qaeda represents will not go away soon. The ideology will survive in some form as wars in Africa, Asia, and the Middle East continue to rage.

Seth G. Jones is director of the International Security and Defense Policy Center at the nonprofit, nonpartisan RAND Corporation, adjunct professor at Johns Hopkins University, and author, most recently, of “Waging Insurgent Warfare: Lessons from the Vietcong to the Islamic State” (Oxford). This article is adapted from testimony the author gave to the House Homeland Security Committee, Subcommittee on Counterterrorism and Intelligence, on July 13, 2017.

This commentary originally appeared on Foreign Affairs on August 7, 2017. Commentary gives RAND researchers a platform to convey insights based on their professional expertise and often on their peer-reviewed research and analysis.

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